S-91837A250 1/4"-28 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance through distorted top thread locking technology that maintains secure fastening under dynamic loads
• Enhanced corrosion protection with zinc-plated steel construction for extended service life in demanding environments
• Reliable Grade 2 strength providing consistent performance for industrial applications requiring dependable locking solutions
• Precision UNF fine threads (1/4"-28) ensuring smooth engagement and optimal clamping force distribution
• Easy installation and removal with standard 7/16" external hex drive compatible with common wrench tools
• Class 2B thread fit guaranteeing proper mating with corresponding male threads for secure assemblies
• Right-hand threading following industry standards for straightforward installation in conventional applications

Professional Applications & Engineering Value

This 1/4"-28 UNF top lock nut addresses critical vibration-induced loosening challenges in industrial machinery, automotive assemblies, and precision equipment. The distorted thread locking mechanism at the top creates consistent friction and resistance against rotational forces, eliminating the need for additional locking components. Manufactured from zinc-plated steel, the nut provides essential corrosion resistance while maintaining Grade 2 strength requirements. The fine UNF threads offer superior load distribution compared to coarse threads, making this external hex locknut ideal for applications where space constraints and vibration exposure demand reliable, maintenance-free fastening solutions that withstand operational stresses without compromising performance.

Specification Summary & Compliance

This locknut features precision 1/4"-28 UNF fine threads with Class 2B thread fit tolerance, ensuring compatibility with standard mating components. The external hex drive measures 7/16" across flats with a 7/32" height profile. Manufactured to industrial standards, the product is fully REACH (EC 1907/2006) compliant and meets RoHS 3 (2015/863/EU) requirements, confirming adherence to environmental and safety regulations for industrial use. The Grade 2 strength classification guarantees consistent mechanical performance across applications requiring reliable distorted thread locking functionality.